2500HD with 6.6 gas

[jdbunch1630]

The best part is the new 6 way tailgate for the GMC comes on the 2020 Heavy Duty's, that and the new 6.6 gas is going to make me want to spend some money !!!
I like the look of the GMC's so much better

[mopwr4me2003]

Originally Posted by jdbunch1630

The best part is the new 6 way tailgate for the GMC comes on the 2020 Heavy Duty's, that and the new 6.6 gas is going to make me want to spend some money !!!
I like the look of the GMC's so much better

As nice and functional that the tailgate seems to be I see nothing but issues here in the northern states that use 100 lbs of salt per square inch [emoji16]

[robbiels7]

Ok thanks for the heads up. I guess im guilty of eye balling the duramax trucks.

Originally Posted by mopwr4me2003

6.6 gas only has the 6 speed trans. The 10 speed is the diesel.

[Hersbird]

Originally Posted by CurtPutnam

The real issue is not whether or not the new engine will pull the trailer anywhere including mountains because it will. The real issue is whether or not to bet on an as yet unproven engine.

It's not an unproven engine, it is a LS small block that has been around since the 90s. It is basically a 6.2 with an iron block an a different stroke in the crank. The direct injection has been around on these since 2015.
This is all great news as I'm sure a 6.6 crate motor will show up in the catalogs and anybody with even a 5.3 will be able to drop one in. Don't want direct injection? No problem to change it to an older system (although I sure wouldnt) want a supercharger? The Caddy, Camaro, or Vette system will basically bolt right on. This 6.6 is just another great tool in the chest that is the new chevy small block.

[dannyabear]

LS crate engines are available up to a 7.3 lt/454 cu in; still not a fan of direct injection or collapsing lifters to drop cylinders

[CurtPutnam]

Originally Posted by Hersbird

It's not an unproven engine, it is a LS small block that has been around since the 90s. It is basically a 6.2 with an iron block an a different stroke in the crank. The direct injection has been around on these since 2015.
This is all great news as I'm sure a 6.6 crate motor will show up in the catalogs and anybody with even a 5.3 will be able to drop one in. Don't want direct injection? No problem to change it to an older system (although I sure wouldnt) want a supercharger? The Caddy, Camaro, or Vette system will basically bolt right on. This 6.6 is just another great tool in the chest that is the new chevy small block.

Good to know. New engines or even combinations just give me a hincky feeling. I've been burned before. The "new" factor is just something to think about.

[FlaNative]

My stock '05 Sierra 2500 HD Diesel is great in the mountains: Diesel is king when it comes to towing in the mountains. Gassers just don't have the torque. Get a diesel: you'll never regret it!

[mopwr4me2003]

Originally Posted by Jimmy James

My stock '05 Sierra 2500 HD Diesel is great in the mountains: Diesel is king when it comes to towing in the mountains. Gassers just don't have the torque. Get a diesel: you'll never regret it!

And again the OP doesn’t sound like he wants a diesel I think that’s been covered a few times already.

[ronheater70]

I will say I saw one review of the new 6.6 gasser, on YT and while they gave the truck overall high marks, they came away a lil unimpressed with the performance of it. But that was only one review, so others may have more favorable opinions.

[mopwr4me2003]

Originally Posted by ronheater70

I will say I saw one review of the new 6.6 gasser, on YT and while they gave the truck overall high marks, they came away a lil unimpressed with the performance of it. But that was only one review, so others may have more favorable opinions.

If the video you talk about is like a lot of the videos out there they keep comparing it to the diesel every time. Well duh it’s a gas and does not have what the diesel does. It’s almost like they are trying to push the diesel more. Not only that most of the videos are with the high country model as well. Oh boy lol

[babock]

Originally Posted by dannyabear

LS crate engines are available up to a 7.3 lt/454 cu in; still not a fan of direct injection or collapsing lifters to drop cylinders

Technically, the LS engines are are small blocks. The 7.4L was not an LS. Neither is the 6.0 or 6.6 although they may have been loosely based on them when they were designed.

[babock]

Originally Posted by dannyabear

LS crate engines are available up to a 7.3 lt/454 cu in; still not a fan of direct injection or collapsing lifters to drop cylinders

Technically, the LS engines are are small blocks. The 7.4L was not an LS. Neither is the 6.0 or 6.6.

Was kinda hoping GM would finally put a turbocharged option in the heavy duty trucks in a gas version.

The new 6.6L engine has direct injection. Sure hope they do what Toyota and Ford does and add some sort of port injectors in there as well to keep the intake valves clean. That's a huge direct injection engine issue.

Interesting that the new Ford 7.3L engine is going to be port injection.

[mopwr4me2003]

The new 6.6 is a small block. Watch the videos straight from GM they say it’s a small block. Watch this.

https://youtu.be/IEBiVx8RW1o

[babock]

Apparently, the 6.6 is an LS engine.

https://en.wikipedia.org/wiki/LS_bas...l-block_engine

[Hersbird]

Originally Posted by babock

Technically, the LS engines are are small blocks. The 7.4L was not an LS. Neither is the 6.0 or 6.6 although they may have been loosely based on them when they were designed.

The 6.0 is an LS also, just with an iron block. Tons of guys use the 6.0 shortblock in their vette or camaro builds swapping all of their heads, intakes, exhaust, oil pan etc, as the 6.0 iron block will take big power adders like nitros, blowers and turbos. Not to mention they are plentiful and cheep. So 4.8, 5.3, 5.7 (not the old 350 though), 6.0, 6.2, and now 6.6 all have almost completely interchangeable components from mid 90's to 2020.

PS i did miss a few sizes the 7.0 and the 7.4, so technically there is a small block LS 7.4 but it is an performance catalog part, not in any production cars. the 7.0 is the LS7 Vette

[linedriver]

Originally Posted by Hersbird

The 6.0 is an LS also, just with an iron block. Tons of guys use the 6.0 shortblock in their vette or camaro builds swapping all of their heads, intakes, exhaust, oil pan etc, as the 6.0 iron block will take big power adders like nitros, blowers and turbos. Not to mention they are plentiful and cheep. So 4.8, 5.3, 5.7 (not the old 350 though), 6.0, 6.2, and now 6.6 all have almost completely interchangeable components from mid 90's to 2020.

PS i did miss a few sizes the 7.0 and the 7.4, so technically there is a small block LS 7.4 but it is an performance catalog part, not in any production cars. the 7.0 is the LS7 Vette

Went to the dealer today, going to trade my 2014 2500hd on a 2020 with the 6.6 gas. Drove one and the power is impressive for a gas engine.

[mopwr4me2003]

Originally Posted by linedriver

Went to the dealer today, going to trade my 2014 2500hd on a 2020 with the 6.6 gas. Drove one and the power is impressive for a gas engine.

[emoji106] let us know how you like it when you start towing with it.

[Hclarkx]

Originally Posted by linedriver

Has anyone driven the new 2500hd with the 6.6 gas engine? I am thinking of up grading next spring. Not sure I want to spend the extra for a duramax. Towing a 7600 lb Coachmen Freedom Express Liberty.

I have one but haven't towed yet. My 5er is about 8700# max and in five years with a 2015 6.0L 4.11 I ONLY complained when we were above 10,000 feet. The only time altitude power was more than a just a nuisance, was on a 20% grade at 11,500 feet. That was scary, creeping at 3 grand in first with pedal to the metal. I almost went to 4WD low in spite of being on pavement. This experience was not nearly enough to make me want to go diesel in the 2020.

With variable valve timing, direct injection, and compression up from 9.7 to 10.8, the new 6.6 should be just fine even limited to 3.73 gears. Rated HP and torque peaks are 200 rpm lower but I read that down around 2K the torque is higher than the 6.0 so maybe it has higher HP from 1500 to 3000 where the 4.11 gears would be most useful.

When cruising, my 6.0 was close to getting into 6th gear but would not stay there long if it did or I forced it there by switching off the tow/haul for a few seconds. I'm hoping that 3.73's will put 5th gear a bit closer to where 6th was in the 6.0 and thus help mpg. The VVT and DI and higher CR should all help mpg as well.

[linedriver]

Originally Posted by Hclarkx

I have one but haven't towed yet. My 5er is about 8700# max and in five years with a 2015 6.0L 4.11 I ONLY complained when we were above 10,000 feet. The only time altitude power was more than a just a nuisance, was on a 20% grade at 11,500 feet. That was scary, creeping at 3 grand in first with pedal to the metal. I almost went to 4WD low in spite of being on pavement. This experience was not nearly enough to make me want to go diesel in the 2020.

With variable valve timing, direct injection, and compression up from 9.7 to 10.8, the new 6.6 should be just fine even limited to 3.73 gears. Rated HP and torque peaks are 200 rpm lower but I read that down around 2K the torque is higher than the 6.0 so maybe it has higher HP from 1500 to 3000 where the 4.11 gears would be most useful.

When cruising, my 6.0 was close to getting into 6th gear but would not stay there long if it did or I forced it there by switching off the tow/haul for a few seconds. I'm hoping that 3.73's will put 5th gear a bit closer to where 6th was in the 6.0 and thus help mpg. The VVT and DI and higher CR should all help mpg as well.

The 6.6 gas has more up and almost as much torgue as the 03 Duramax I had.

[babock]

Too bad it doesn't have as much HP and torque as my 3.5 Ecoboost

Originally Posted by linedriver

The 6.6 gas has more up and almost as much torgue as the 03 Duramax I had.